SYNOPSIS ?C ABSTRACT Twenty-seven healthy@ adult male and female volunteers were exposed to carbon monoxide at concentrations of lt; 2@ 50@ 100@ 200 and 500 ppm for periods up to 4j hours for the purpose of determining the effect of the gas upon time perception. These exposures@ which resulted in a range of carboxyhemoglobin saturations up to 20%@ produced no impairment in the ability of the subjects to perform the Beard-Wertheim Time Discrimination Test@ to estimate ten or thirty second intervals@ or to perform the Marquette Time Estimation Test. The first untoward effect of carbon monoxide (CO) upon healthy man is reported to be a gross impairment in his ability to distinguish between short intervals of time and to estimate 30-second intervals. Alarmingly@ these decrements in time perception are reported to be produced by exposures to CO at concentrations as low as 50 parts per million (ppm) for 90 minutes@ exposures which are currently acceptable in American industry@ commonly encountered by urban populations@ and much lower than those experienced by the average adult smoking one pack of cigarettes per day. The implications of these CO induced decrements were judged to be of such critical importance that two independent research groups conducted similar@ though not identical@ time perception experiments in an attempt to corroborate the observations of the original investigators@ Beard and Wertheim. Neither independent research group was able to do so. Meanwhile@ major review articles dealing with the toxic effects of CO upon man listed the time perception impairment as an early untoward effect of CO exposure. The issue became more confused when Dr. Beard announced that he was unable to reproduce his original findings. In an effort to gain additional information as to the precise effect of CO upon human time perception@ a comprehensive investigation was undertaken which included a series of time tests performed under conditions identical to those reported by Beard and Wertheim in their original work. This investigation is the subject of this report.
API 4159-1970 history
1970API 4159-1970 THE EFFECT OF CARBON MONOXIDE ON TIME PERCEPTION